On 3 May 1917, during the Nivelle Offensive, the French 2nd Colonial Division, veterans of the Battle of Verdun, refused orders, arriving drunk and without their weapons. Their officers lacked the means to punish an entire division, and harsh measures were not immediately implemented. The French Army Mutinies eventually spread to a further 54 French divisions, and 20,000 men deserted.
In two days the British and Indian infantry, supported by a creeping barrage, broke the Ottoman front line and captured the headquarters of the Eighth Army (Ottoman Empire) at Tulkarm, the continuous trench lines at Tabsor, Arara, and the Seventh Army (Ottoman Empire) headquarters at Nablus.
In May 1917, Garvey launched a New York branch of UNIA. He declared membership open to anyone "of Negro blood and African ancestry" who could pay the 25 cents a month membership fee. In his speeches, he sought to reach across to both Afro-Caribbean migrants like himself and native African-Americans. Through this, he began to associate with Hubert Harrison, who was promoting ideas of black self-reliance and racial separatism.
In the wake of the East St. Louis Race Riots in May to July 1917, in which white mobs targeted black people, Garvey began calling for armed self-defense. He produced a pamphlet, "The Conspiracy of the East St Louis Riots", which was widely distributed; proceeds from its sale went to victims of the riots. The Bureau of Investigation began monitoring him, noting that in speeches he employed more militant language than that used in print; it for instance reported him expressing the view that "for every Negro lynched by whites in the South, Negroes should lynch a white in the North".